Rubio Leticia, Martinez Luis J, Martinez Esther, Martin de las Heras Stella
Department of Forensic Medicine and Forensic Odontology, University of Granada, Granada 18071, Spain.
J Forensic Sci. 2009 Nov;54(6):1411-3. doi: 10.1111/j.1556-4029.2009.01159.x. Epub 2009 Oct 5.
DNA degradation can interfere with the resolution of forensic cases. Allelic dropout often reduces the opportunity for adequate comparisons between degraded and reference samples. This study analyzed DNA degradation in 24 extracted teeth after storage at room temperature for 0, 2, 5, and 10 years. DNA concentration, quantified by dot-blot hybridization, declined significantly for the first 2 years, but there was no significant further degradation from the second to the tenth year of storage. COfiler analysis was used and the allelic dropout ratio for the amelogenin locus relative to CSF1PO locus was also estimated. Statistically significant differences were found between fresh teeth and teeth from the 2- and 5-year groups but not from the 10-year group. Under our storage conditions most of the DNA degradation occurred during the first 2 years. Further research is needed to control for individual and external factors that could affect DNA.
DNA降解会干扰法医案件的侦破。等位基因脱失常常减少了对降解样本与对照样本进行充分比对的机会。本研究分析了24颗拔除牙齿在室温下保存0年、2年、5年和10年后的DNA降解情况。通过斑点杂交法定量的DNA浓度在保存的前2年显著下降，但从第2年到第10年没有进一步的显著降解。使用COfiler分析法，并估算了牙釉蛋白基因座相对于CSF1PO基因座的等位基因脱失率。发现新鲜牙齿与保存2年和5年组的牙齿之间存在统计学上的显著差异，但与保存10年组的牙齿之间没有差异。在我们的保存条件下，大部分DNA降解发生在最初的2年。需要进一步研究以控制可能影响DNA的个体因素和外部因素。
